The post about QLD reg's is right...you can leave the old sticker on until a new one turns up. My last car had a rego date of the 30th of the month, and it always took up to two or three weeks for the next sticker to arrive...I used to be worried driving around halfway into the next month with an out of date sticker...
really obvious....

...but nothing ever happened.
Apparently it is an offence to just sound your horn to say "hi" to someone, even beeping the horn as you drive off for work, and if the orificer was feeling a real prick he
could book you for it legally.
I have "fought the law", and yes, the "law won"...I pulled away from work on my bike one evening, (everyone drives steadily down this road, as it is a known haunt of the radar trap boys) out onto the main road from the parking area, and had just straightened up to head into town and wasn't even in third gear when down the road I saw a cop step out onto the road in a reflective vest waving a red torch. I thought maybe there'd been an accident or it was a random breath test, but no...he was booking me for 72 in a 60 zone...here's the figure on the laser radar to prove it. I was booked "140 meters from his position", as the laser gives the distance away where you were clocked doing the speed. I said, naturally, "bull****", and he said no, they don't make mistakes. I said I would fight it, and he told me to go to the cop station and fill out a statutory declaration. The next day I borrowed one of those wheels on a stick that measures out meters from work, and found that my parking spot was 143 meters from where the cop had been set up...so from a standstill I accelerated to 72 km/hr in three meters...sorry, but look as hard as I can I haven't noticed the rocket boosters on the back of my bike...
The girl at the counter in the cop shop was amazed when I told her the story, and said she would fight it too and was very helpful. I filled out the forms, with a three page version of the events with maps drawn and distances marked out. I was told not to pay the fine but to wait. Three months later I finally got a reply..."pay up, we're right, you're wrong".
Mates at work wanted me to take it to court, but what for? To lose a days pay and end up still having to pay the fine plus costs? I don't think so.
Laser is infallible, everyone knows that....